The invention relates to a sort of additive composition used for manual gearbox oil, especially to the lubrication oil of truck gearbox. It belongs to the technical field of lubricating oil additives.
The compound agent for manual gearbox oil is used to prepare the oil of manual truck gearboxes of every viscosity brand and meets the international standards of API MT-1 for the manual truck gearbox oil. The additional volume of the agent is one of the most important indexes to evaluate the quality, efficiency and technology of the additive. In the prior art, the manual gearbox oil additive published in U.S. Pat. No. 5,763,372 comprises alkyl succinimide, sulphate and phosphorous antiwear agent. However, it is different from the composition of the present invention. Also, the Chinese Patent application Nos. 97112341.1 and 97112340.3 refer to the manual gearbox oil and the compound agent thereof, but in comparison with the present invention, the additional volume of the said compound agent is much higher, and that compound agent of the manual gearbox oil cannot meet the requirement of the specification standards of API MT-1.
An object of the present invention, therefore, is to provide a sort of additive composition that can be used in various types of basic oil. Manual truck gearbox oil of 90, 140, 85W/90, 85W/140, 80W/90, 80W/140 and 75W/90 mixed with the composition of the present invention can meet the specification standards of API MT-1.
In order to realize all the above-mentioned objects, each component in the additive composition is deliberately chosen. Not only are the properties and advantage of every component taken into consideration, but priority is also given to the thermal stability, rust-resisting quality and endurance of the component. The performance of every component in the additive cannot realize the above-mentioned objectives alone. It is necessary to research the performance of every component so as to make the additive superior to the prior art.
In the present invention, the amount of sulfur in the product is 26-30%, that of phosphorous is 1.5-2% and nitrogen 0.2-0.6% based on the total quality of the additive composition. It is of good thermal stability, rust-resisting quality and endurance. The oil of various viscosities such as 90, 140, 85W/90, 85W/140, 80W/90, 80W/140, 75W/90 mixed with 2.4% of the present additive composition meets the specification standards of API MT-1. The present additive composition has low expense of use and production, and the product represents good economic and social benefits. Being easy to use and of excellent performance, it has a bright market expectation.
In a preferred embodiment, an additive composition designed for manual gearbox oil of the present invention based on the total quality of the composition comprises:
An isobutylene sulfide in an amount of 40-90%;
A zinc dialklydithiophosphate and the derivative thereof in an amount of 1-20%;
A component selected from the group consisting of phosphite ester and the derivative thereof, phosphate and the derivative thereof, and the randomly combined mixture thereof in an amount of 10-40%;
A component selected from the group consisting of benzotriazole fatty amine salts and the derivative thereof, sulfurized oxomolybdenum dialkydithiophosphate and the derivative thereof, fatty acid ester and its boride, and the randomly combined mixture thereof in an amount of 0.5-10%;
A component selected from the group consisting of succinimide and its boride, organic sulfonate, fatty acid amide and its boride, and the randomly combined mixture thereof in an amount of 2-15%; and
A component selected from the group consisting of ester borate and its derivative, amine antioxidant, phenol antioxidant, and the randomly combined mixture thereof in an amount of 0.5-10%.
In other words, the present additive composition in a preferred embodiment of the present invention comprises the following components: component (A) at least sulfur-containing extreme pressure (Ep) antiwear agents; component (B) at least an antioxidant and anticorrosive agent; component (C) at least phosphorous antiwear agent; component (D) at least a friction modifier; component (E) at least an antirusting agent; and component (F) at least an antioxidant agent. The said component (A) is preferably isobutylene sulfide in amount of 40-90%, more preferably 40-80% based on the total quantity of the composition. The said component (B) is preferably zinc dialklydithiophosphate and its derivative in amount of 1-20%, more preferably 1-15% based on the total quantity of the composition. The said component (C) is preferably phosphite ester and its derivative, phosphate and its derivative, or the mixture thereof in amount of 10-40%, more preferably 10-30% based on the total quanity of the composition. Moreover, the acidic phosphite ester or neutral phosphite ester or the mixture thereof is preferably for the component (C). The component (D) is preferably benzotriazole fatty amine salts and its derivative, sulfurized oxomolybdenum dialkydithiophosphate and its derivative, alicyclic ester and its boride, or the randomly-combined mixture thereof in amount of 0.5-10%, more preferably 1-8%, based on the total quantity of the composition. The said component (E) is preferably succinimide and its boride, organic sulfonate, fatty acid amide and its boride, or the randomly combined mixture thereof in amount of 2-15%, more preferably 2-10% based on the total quality of the composition. The said component (F) is preferably borate ester and its derivative, amine antioxidant, phenol antioxidant, or the randomly combined mixture thereof in amount of 0.5-10%, more preferably 1-8% based on the total quantity of the composition.
Therefore, it is very clear for the composition of the present invention to contain (A) a sort of sulphide Ep antiwear agent; (B) a sort of antioxidant and antiseptic agent; (C) a sort of phosphorous antiwear agent; (D) a sort of friction modifier; (E) a sort of antirust agent; and (F) a sort of antioxidant agent.
According to a preferred embodiment of the present invention, a method for preparation of the additive composition comprises the steps of proportionally mixing the said component (A) as the Ep antiwear, the said component (C) as antiwear and the said component (D) as friction modifier in an enamel kettle with a mixer; then proportionally putting the said component (B) as antioxidant and antirusting, the said component (E) as antirusting, and the said component (F) as antioxidant into the kettle in order to get a mixture in the temperature of 60-70xc2x0 C. along with mixing for 4 hours until the mixture is dissolved completely and becomes evenly transparent.
For choosing the components of the additive composition, two laboratories are used to simulate and evaluate the efficiency of the product with several experimental methods, including Lubricating Oil Ep Test (GB/T 3142) and Lubricating Oil Antiwear Test (SH/T0189).
For evaluating whether the additive composition conforms to the API MT-1 specification standards after adding it into the basic oil, the Copper Stain Test for petroleum products (GB/T5096 or ASTM D130), Lubricating Oil Carrying Capacity Test (CL-100) (SH/T0306 or ASTM D5182), Gear Oil Thermal-Oxidative Stability Test (L-60, L-60-1), Gear Oil High-Temperature Stability Test (ASTM D5579), Adaptability to Sealing Material Test (ASTM D5662), and Lubricating Oil Foam Resistance Test (ASTM D 892) are carried out separately.